Luck was on Austin Prep’s side in a 2-1 victory over St. John’s Prep in
the Super 8 semifinals at the Tsongas Center Wednesday night. The Cougars got some help from a St. John’s Prep defender, who inadvertently swatted the puck into his own net with his glove for the winning goal with 2:11 left in the third period.

The top-seeded Eagles (19-4-1) spent more time in the attacking zone, outshooting the Cougars, 29-21, but their offense was stale, shots pinged off the posts, and chances went unconverted.

The Cougars (16-1-6) will play two-time defending champion Malden Catholic on Sunday at 6 p.m. at TD Garden with a chance to become just the seventh school to win the Super 8 in its 23-year existence.

“I think when things are going well for you, you get the bounces,” said Austin Prep coach Lou Finocchiaro.

In a sloppy first period, that neither coach was happy with, Austin Prep sophomore goalie Elijah Harris dueled St. John’s Prep senior Billy Price, who did stymie Harris was quick across his crease to stop a two-on-one chance, kicking away Andrew Brandano’s shot with his left skate. Price then one-upped Harris made a shoulder save on a breakaway chance from the Cougars’ leading scorer, Vesey (20 goals) on a breakway.

Vesey struck in the second period when a deflection off a shot from Eric MacAdams landed on his tape for a simple put-away. After a failed power play, the The Eagles struck in the third when Tyler Bird collected a loose puck in the slot and beat a screened Harris. with a low-side shot.

Then Bob Carpenter, the son of ex-Bruin Bobby Carpenter, fired the slap shot that was thrown by a Prep player into the Eagles’ net.

Vesey was credited with the goal.

“I don’t even know how it went in,” he said. “Cam Russo tipped it, it went up in the air, my stick went up, the kid’s glove went up, we both kind of hit it and it went in. Lucky bounce, but we’ll take it for sure.”

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